rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (0 ticks this GP) idle=e174/1/0x4000000000000000 softirq=207736/207736 fqs=3
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5831/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=176705, q=565 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7044 Comm: syz-executor Not tainted 6.15.0-rc6-syzkaller-00105-g088d13246a46 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4856 [inline]
RIP: 0010:__lock_acquire+0x1f9/0x1ba0 kernel/locking/lockdep.c:5185
Code: ff 1f 00 00 41 09 c5 8b 84 24 c0 00 00 00 44 89 6b 20 89 43 24 e8 f7 b0 ff ff 48 89 df 44 0f b6 a8 c4 00 00 00 e8 e7 b0 ff ff <0f> b6 b0 c5 00 00 00 45 84 ed 0f 84 fb 01 00 00 0f b6 4b 21 84 c9
RSP: 0018:ffffc90000007c48 EFLAGS: 00000003
RAX: ffffffff95aac4d8 RBX: ffff88802dc82f58 RCX: 0000000000020000
RDX: 0000000000000000 RSI: ffff88802dc82f30 RDI: ffff88802dc82f58
RBP: ffff88802dc82f30 R08: 0000000000080000 R09: 0000000000000001
R10: 0000000000000000 R11: ffffffff8e3bfc00 R12: 0000000000000001
R13: 0000000000000003 R14: ffff88802dc82440 R15: 0000000000000000
FS: 0000555593833500(0000) GS:ffff8881249df000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555898b5808 CR3: 000000006966c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire kernel/locking/lockdep.c:5866 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
advance_sched+0x699/0xc80 net/sched/sch_taprio.c:985
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x202/0xad0 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
__sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1055
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rcu_is_watching+0x0/0xc0 kernel/rcu/tree.c:732
Code: a2 3c 8e e8 e2 00 62 03 e9 51 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 53 65 ff 05 d3 1f 03 12 e8 2e 1c cc 09 48 c7 c3 e8
RSP: 0018:ffffc90004b6f658 EFLAGS: 00000297
RAX: 0000000000000000 RBX: ffffffff8e3bfc00 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e3bfc00
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000011096 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0x2cd/0x350 kernel/locking/lockdep.c:5829
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2380 [inline]
slab_free mm/slub.c:4642 [inline]
kmem_cache_free+0x2d4/0x4d0 mm/slub.c:4744
va_clip mm/vmalloc.c:1645 [inline]
va_alloc mm/vmalloc.c:1747 [inline]
__alloc_vmap_area mm/vmalloc.c:1783 [inline]
alloc_vmap_area+0x1ecc/0x2970 mm/vmalloc.c:2000
__get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3138
__vmalloc_node_range_noprof+0x277/0x1540 mm/vmalloc.c:3805
vmalloc_user_noprof+0x6b/0x90 mm/vmalloc.c:3997
kcov_ioctl+0x4c/0x730 kernel/kcov.c:716
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl fs/ioctl.c:892 [inline]
__x64_sys_ioctl+0x193/0x200 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd71178e56b
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007fff011064c0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000080000 RCX: 00007fd71178e56b
RDX: 0000000000080000 RSI: ffffffff80086301 RDI: 00000000000000dc
RBP: 00007fd7119b63b8 R08: 00000000000000da R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
task:syz-executor state:R running task stack:23512 pid:5831 tgid:5831 ppid:5813 task_flags:0x400140 flags:0x00000000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6947
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
copy_pte_range mm/memory.c:1194 [inline]
copy_pmd_range mm/memory.c:1255 [inline]
copy_pud_range mm/memory.c:1292 [inline]
copy_p4d_range mm/memory.c:1316 [inline]
copy_page_range+0x1948/0x5f80 mm/memory.c:1410
dup_mmap kernel/fork.c:726 [inline]
dup_mm kernel/fork.c:1734 [inline]
copy_mm kernel/fork.c:1786 [inline]
copy_process+0x862b/0x91a0 kernel/fork.c:2429
kernel_clone+0xfc/0x960 kernel/fork.c:2844
__do_sys_clone+0xce/0x120 kernel/fork.c:2987
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbb653851d3
RSP: 002b:00007ffcae916b38 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbb653851d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055558551b7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000e85e4 R15: 00007ffcae916cd0
rcu: rcu_preempt kthread starved for 10495 jiffies! g176705 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:R running task stack:27704 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 5826 Comm: syz-executor Not tainted 6.15.0-rc6-syzkaller-00105-g088d13246a46 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline]
RIP: 0010:cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline]
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x4a3/0x1290 kernel/smp.c:885
Code: e5 01 89 ee e8 de 12 0c 00 85 ed 74 48 48 8b 44 24 20 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 7d 17 0c 00 90 41 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 de 0b 00 00 8b 43
RSP: 0018:ffffc9000469f8b8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b8441720 RCX: ffffffff81af2ee9
RDX: ffff888025072440 RSI: ffffffff81af2ec3 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170882e5
R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b853b040
FS: 00005555898b5500(0000) GS:ffff888124adf000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f107eee56c0 CR3: 000000006063a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1291 [inline]
flush_tlb_mm_range+0x322/0x1780 arch/x86/mm/tlb.c:1381
dup_mmap kernel/fork.c:765 [inline]
dup_mm kernel/fork.c:1734 [inline]
copy_mm kernel/fork.c:1786 [inline]
copy_process+0x7961/0x91a0 kernel/fork.c:2429
kernel_clone+0xfc/0x960 kernel/fork.c:2844
__do_sys_clone+0xce/0x120 kernel/fork.c:2987
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f107e1851d3
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffda10797f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f107e1851d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555898b57d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000e8629 R15: 00007ffda1079990